Liquid crystal display devices (LCDs) include: the TN (Twisted Nematic) mode liquid crystal display device, in which a pixel electrode (picture element electrode) is provided on one of a pair of substrates (an upper substrate and a lower substrate) between which a liquid crystal layer is interposed, and a counter electrode on the other, such that displaying is performed by controlling the orientation of liquid crystal within a plane which is perpendicular to the substrate plane in accordance with an electric field occurring between both electrodes; and the FFS (Fringe-Field Switching) mode liquid crystal display device and the IPS (In-Plane Switching) mode liquid crystal display device, in which a pixel electrode and a counter electrode (lower electrode) are provided on one of a pair of opposing substrates, such that displaying is performed by controlling the orientation of liquid crystal within a plane which is substantially parallel to the substrate plane.
Moreover, liquid crystal display devices include: the transmission-type liquid crystal display device which utilizes backlight from behind the display panel as a light source for displaying; the reflection-type liquid crystal display device which utilizes reflected light of external light; and the transflective-type liquid crystal display device (reflection/transmission-type liquid crystal display device) which utilizes both reflected light of external light and backlight. The reflection-type liquid crystal display device and the transflective-type liquid crystal display device are characterized in that they have smaller power consumptions than that of the transmission-type liquid crystal display device, and their displayed images are easy to see in a bright place. The transflective-type liquid crystal display device is characterized in that its screen is easier to see than that of the reflection-type liquid crystal display device, even in a dark place.
FIG. 31 is a cross-sectional view showing the construction of a lower substrate 100 of a conventional FFS mode transflective-type liquid crystal display device which is described in Patent Document 1.
As shown in FIG. 31, the lower substrate 100 includes a TFT region, a transmission region, and a reflection region. In the TFT region, a gate electrode 103, an active layer 106, a source/drain electrode 107, and the like are formed on an organic resin film 101. In the transmission region and the reflection region, a counter electrode 102, a pixel electrode 105, and the like are formed. A plurality of slits are formed in the pixel electrode 105, such that the orientation of liquid crystal (not shown) which is disposed on the lower substrate 100 is controlled in accordance with a voltage or an electric field which is applied between electrode portions interposed between slits and the counter electrode 102.
Between the counter electrode 102 and the pixel electrode 105 in the reflection region, a reflector 109 for reflecting incident light is provided. In the transmission region, the counter electrode 102 is provided in contact with the substrate 110; however, in the reflection region, the counter electrode 102 is formed on the organic resin film 101 disposed on the substrate 110. An emboss pattern is formed by etching on an upper face of the organic resin film 101 in the reflection region, and a plurality of protrusions (or recesses) are formed on the counter electrode 102 so as to conform to the shape of this upper face.
[Patent Document 1] Japanese Laid-Open Patent Publication No. 2006-317905